Global Analysis of Streamflow Return Periods Using GRDC Data and Bootstrapping Techniques

Understanding streamflow extremes is essential for effective water resource management and disaster risk reduction. This study uses the Global Runoff Data Centre (GRDC) database, comprising daily discharge records from stations worldwide, to calculate return periods for streamflow extremes using L-moments and bootstrapping techniques. Bootstrapping techniques were employed to enhance the robustness of return period estimates by quantifying uncertainties and providing confidence intervals, ensuring more reliable insights into streamflow extremes across diverse hydrological contexts, particularly when there are numerous stations with limited or incomplete observations.

In this study, we analyze the multi-decadal changes and trends in streamflow extremes for different climatic zones across the globe. The temporal trends indicate potential shifts in return periods, suggesting the possible influence of climate variability. Regional anomalies highlight localized hydrological phenomena, emphasizing the importance of spatially explicit analyses.

The results have broad implications for flood and drought risk assessment, water resource planning, and climate adaptation strategies. By providing a global perspective on hydrological extremes, this study contributes to an improved understanding of streamflow variability and offers critical benchmarks for future hydrological modeling and climate impact assessments.